One way in which digital media may be distributed to a consumer is commonly referred to as “streaming.” Digital media data may be transmitted from a server to a client over a one or more computer networks. When a client requests a digital media file from a server, the client typically provides the server with the address of the media file, such as the Universal Resource Locator (URL) of the media file. The server then accesses the media file and sends it to the client as a continuous data stream. Streaming media is often sent in compressed form over the network, and is generally played by the client as it arrives. With streaming media, client users typically do not have to wait to download a large media file before seeing and/or hearing the media file. Instead, the data from a media file is sent in a continuous stream and is played as it arrives.
Many devices within a home network contain various types of digital media content that other devices would like to access. As an example, a personal computer and/or personal video recorder might contain a significant portion of the homeowner's audio, video, and still-image library. Such “media server” devices may be equipped with an implementation of a “content directory service.” The content directory service allows the homeowner to browse the content that is accessible to the media server, select a specific piece of content, and cause it to be played on an appropriate rendering device (e.g., an audio player for music objects, a TV for video content, an Electronic Picture Frame for still-images, etc). For maximum convenience, it is desirable to allow the homeowner to initiate these operations from a variety of consumer electronic devices, such as personal computers, televisions, set-top boxes, PDAs, DVD/CD players, MP3 players, stereo systems, VCRs, camcorders, digital cameras, etc.
In order to be compatible with as many client devices in the UPnP home network as possible, a media server device may be configured to perform protocol and/or format conversion of media content. For example, consider an Internet radio station using RTSP/RTP/UDP. To accommodate client devices that can only play via HTTP, a media server could provide protocol translation from RTSP/RTP/UDP to HTTP. Format conversion is required by some home networking standards like Digital Entertainment Network Initiative (DENi), Consumer Electronics Association (CEA) R 7.6 Digital Entertainment Network (and likely Digital Home Working Group—DHWG) which are built using Universal Plug and Play (UPNP) technology. These standards require that a UPnP AV Media Server transcode the media content to a common format to support a UPnP AV Media Renderer (e.g., a DENi media player), which otherwise may not have the ability to decode some media types. The ability of a media server device to perform transcoding and/or protocol translation improves interoperability and is therefore beneficial from the consumer point of view.
When media data from a media file is streamed from a media server to a client device without transcoding or protocol conversion, this is referred to as an “original stream.” When transcoding and/or protocol conversion are performed, this is referred to as a “non-original stream.” The media server expends computational resources to perform protocol translation and/or transcoding. In addition, the quality of a transcoded stream is typically worse than the quality of the original stream. Accordingly, benefits may be realized by systems and methods for identifying ways for client systems to access an original stream of media content.